METTLER TOLEDO FE28-Standard Benchtop pH Meter

Overview

The METTLER TOLEDO FE28-Standard is a high-performance benchtop pH meter engineered for precision, repeatability, and compliance in routine laboratory and quality control environments. Based on potentiometric measurement principles, it determines hydrogen ion activity via a glass electrode coupled with a reference system—delivering stable, traceable readings across aqueous and semi-aqueous matrices. Unlike portable variants, the FE28-Standard features a fixed benchtop architecture optimized for long-term stability, reduced drift, and integration into regulated workflows. Its dual-mode temperature compensation (automatic or manual) ensures accurate pH values across the full operational range of –2.00 to 16.00 pH and –5 to 105 °C. Designed and manufactured in Germany, the instrument complies with IEC 61010-1 safety standards and supports audit-ready operation in GLP and GMP settings when paired with appropriate documentation protocols.

Key Features

• High-resolution segmented LCD display (4.3 inches) with intuitive icon-based interface for rapid parameter recognition and status verification
• Dual-input electrode connectivity: BNC for pH/mV electrodes and Cinch for integrated NTC 30 kΩ temperature sensors—enabling simultaneous, compensated measurements
• Flexible calibration architecture supporting up to five-point calibration using linear or segmented (non-linear) algorithms; includes four pre-programmed buffer sets (US, NIST, DIN, and China-specific)
• Robust data management: stores 200 measurement records with timestamps, electrode ID (if supported), temperature, and calibration metadata
• Full digital connectivity suite: RS232 and USB interfaces enable direct data export to LIMS or Excel-compatible formats without proprietary software dependency
• Modular design accommodates application-specific electrodes—including LE438 (standard aqueous), LE410 (high-ionic-strength), LE422 (micro-volume), and LE420 (TRIS/oil-emulsion)—all compatible with automatic electrode detection and identification

Sample Compatibility & Compliance

The FE28-Standard demonstrates broad compatibility across sample types encountered in environmental testing, pharmaceutical QC, food & beverage analysis, and academic research. Its extended pH range (–2.00 to 16.00) and robust mV measurement capability (–2000 to +2000 mV) support applications involving strong acids, caustic solutions, and redox-active systems. When used with the LE420 electrode and optional ATC probe (Order No. 12997876), it maintains accuracy in heterogeneous media such as emulsions, crude oils, and TRIS-buffered biological suspensions. The instrument meets ISO/IEC 17025 requirements for measurement uncertainty estimation and supports traceability under ASTM E70, ISO 3696 (Grade 3 water), and USP pH measurement guidelines. While not inherently 21 CFR Part 11 compliant, its data export functionality and timestamped records facilitate integration into validated electronic record systems.

Software & Data Management

No dedicated PC software is required for basic operation—configuration, calibration, and measurement are fully self-contained within the device firmware. However, raw data files (CSV format) exported via USB or RS232 retain full metrological context: date/time stamp, measured value, unit, temperature, electrode type (if encoded), and active calibration profile. This structure enables seamless import into statistical process control (SPC) platforms or laboratory information management systems (LIMS). Audit trails can be reconstructed from stored calibration history and measurement logs, satisfying internal QA requirements for method validation and equipment qualification (IQ/OQ/PQ).

Applications

• Routine pH verification of purified water, buffer solutions, and cleaning agents in pharmaceutical manufacturing (aligned with EU GMP Annex 1 and FDA guidance)
• Quality assurance of dairy products, beverages, and sauces where pH directly correlates with microbial stability and shelf life
• Environmental monitoring of wastewater effluents, soil extracts, and leachates per EPA Method 9040C
• Electrochemical education and research labs requiring reproducible, low-drift measurements across diverse electrolyte compositions
• Biotechnology processes involving TRIS-HCl, phosphate, or citrate buffers—especially when paired with the LE420 electrode and ATC temperature probe

FAQ

Does the FE28-Standard support GLP-compliant data recording?
Yes—when used with timestamped calibration and measurement logging, and combined with external validation of procedures, it fulfills core GLP data integrity requirements.
Can the FE28-Standard be calibrated using Chinese national standard buffer solutions?
Yes—the instrument includes a dedicated Chinese buffer set (pH 4.01, 6.86, 9.18 at 25 °C) compliant with JJG 119-2018 verification regulations.
Is an external temperature probe required for accurate pH measurement?
No—automatic temperature compensation (ATC) is supported natively via integrated NTC 30 kΩ input; however, use of the optional ATC probe (12997876) improves accuracy in non-homogeneous or rapidly changing thermal environments.
What electrode is supplied with the FE28-Standard kit?
The standard configuration includes the LE438 three-in-one pH electrode, optimized for general-purpose aqueous samples with fast response and low maintenance.
Can measurement data be exported in CSV format for regulatory submission?
Yes—USB and RS232 interfaces export fully formatted CSV files containing all relevant metrological parameters, suitable for inclusion in regulatory dossiers or audit packages.